The present invention relates to a rubber mixer which does not release generated contaminants such as dust into a working room, can reduce an amount of the contaminants adhering to a rubber during mixing thereof and can give a clean rubber compound.
Hitherto rubber mixing has been carried out by using a rubber mixer as shown in FIG. 6 to prepare a rubber compound. A rubber mixer 1 usually comprises a driving section 3 comprising a motor 7, an emergency shutdown mechanism (clutch) 8 and a speed reduction mechanism 9 and a rubber mixing section 2 comprising two rubber rolls 4 and bearings 6 supporting rotation shafts 5 of the rolls and having an oil reservoir. The speed reduction mechanism 9 and the rubber mixing rolls 4 to be driven are connected by means of a chain or belt 10. The driving section 3 is covered with a covering 21 and a fan for air-cooling of the motor 7 is provided inside thereof. Air in a working room 14 is taken into the driving section through an air intake part 22 of the covering 21 and is exhausted through an air exhausting part 23 into the working room 14.
In such a rubber mixer, fine particles of metal and oil mist are generated from the motor 7, speed reduction mechanism 9 and bearings 6, and fine particles of metal are generated from the emergency shutdown mechanism 8. Those fine particles of metal and oil mist are spread in the working room 14 by the fan and contaminate air in the working room. If the inside of the working room is contaminated, a clean rubber compound cannot be obtained even if a clean rubber material is used.
An object of the present invention is to provide a dust-free rubber mixer which does not release various dusts (fine particles of metal and oil mist) to be generated from the rubber mixer into the working room.
Namely the present invention relates to a dust-free rubber mixer, in which rubber mixing rolls and a driving section are isolated from the outside atmosphere by means of a casing and an air intake for suction of air into the inside of the casing is provided in a periphery of rotation shafts of the rubber mixing rolls which are contact portion with the casing.
Also the present invention relates to a dust-free rubber mixer comprising a rubber mixing section having a plurality of rubber mixing rolls and a driving section having a motor, in which the whole parts of the rubber mixer except the rubber mixing rolls are covered with a casing, an air intake is provided on the casing in a periphery of rotation shafts of the rubber mixing rolls, an exhaust duct is provided on the casing and air suction means for making the inside pressure of the casing reduced is provided on the exhaust duct.
In the rubber mixer of the present invention, the parts thereof except the rubber mixing rolls are isolated from air in the working room by means of the casing and since the inside pressure of the casing is reduced, dusts generated inside the casing are not released into the working room.
Therefore the rubber mixer of the present invention exhibits a good effect particularly when installed in a clean room.